SICK AND TIRED OF TELKOM

I've been trying to close an account that is no longer in use. I've been trying to contact Telkom, but its impossible to get through to anyone, I ended up getting through to an agent by the name of Kweyizi and she promised to help. Till today. i have sent her numerous emails which she does not respond. They say i owe an amount of R580.00 which according to me and my bank statements prove that i have settled everything. When I do get to speak with someone, its not the right person. This has been going on for months, I don't know what to do anymore, I just want to close the account and move on. They have now flagged my name. I have bad credit record as a result. Please assist. TELKOM RESPOND.